linux/arch/powerpc/include/asm/cpu_has_feature.h

57 lines
1.3 KiB
C

/* SPDX-License-Identifier: GPL-2.0 */
#ifndef __ASM_POWERPC_CPU_HAS_FEATURE_H
#define __ASM_POWERPC_CPU_HAS_FEATURE_H
#ifndef __ASSEMBLY__
#include <linux/bug.h>
#include <asm/cputable.h>
static inline bool early_cpu_has_feature(unsigned long feature)
{
return !!((CPU_FTRS_ALWAYS & feature) ||
(CPU_FTRS_POSSIBLE & cur_cpu_spec->cpu_features & feature));
}
#ifdef CONFIG_JUMP_LABEL_FEATURE_CHECKS
#include <linux/jump_label.h>
#define NUM_CPU_FTR_KEYS BITS_PER_LONG
extern struct static_key_true cpu_feature_keys[NUM_CPU_FTR_KEYS];
static __always_inline bool cpu_has_feature(unsigned long feature)
{
int i;
#ifndef __clang__ /* clang can't cope with this */
BUILD_BUG_ON(!__builtin_constant_p(feature));
#endif
#ifdef CONFIG_JUMP_LABEL_FEATURE_CHECK_DEBUG
if (!static_key_initialized) {
printk("Warning! cpu_has_feature() used prior to jump label init!\n");
dump_stack();
return early_cpu_has_feature(feature);
}
#endif
if (CPU_FTRS_ALWAYS & feature)
return true;
if (!(CPU_FTRS_POSSIBLE & feature))
return false;
i = __builtin_ctzl(feature);
return static_branch_likely(&cpu_feature_keys[i]);
}
#else
static inline bool cpu_has_feature(unsigned long feature)
{
return early_cpu_has_feature(feature);
}
#endif
#endif /* __ASSEMBLY__ */
#endif /* __ASM_POWERPC_CPU_HAS_FEATURE_H */